Hydrogeology, Engineering Geology and Geotechnics THE USE OF HISTORICAL CARTOGRAPHIC AND ICONOGRAPHIC SOURCES IN SEARCH OF ABANDONED OR FORGOTTEN STONE QUARRIES FOR CONSTRUCTION PURPOSES Lucie Arnošová 1), Jiří Bláha 1), Svatoslav Chamra 2), Michal Panáček 3) 1 The Institute of Theoretical and Applied Mechanics AS CR, Centre of Excellence Telč, Czech Republic 2 Czech Technical University in Prague, Department of Geotechnics, Czech Republic 3 National Technical Museum, Prague, Czech Republic ABSTRACT When repairing historic buildings with dressed stone masonry or stone cladding there is often the need for a thorough petrographic and mineralogical analysis of the rock material used, sometimes even including the locating of the quarries from where the rock was originally obtained in the past. However the vast majority of quarries used in the past as a source of building material were abandoned over time. Often they were only small stone pits located in the near surroundings of the construction site. If the stone was not taken from one of the major quarries, whose history is well known and has been described in related literature, there are two options remaining: direct terrain surveys of nearby areas and at times areas further afield or research of possible written and pictorial archival sources. This paper focuses on where to obtain these documents, how they usually look, how to proceed in searching for them and finally how to interpret them. Also some examples of how stone quarries are depicted on old maps and pictures will be shown, including pointing out the historical and contemporary urban planning and landscaping context. Nowadays the situation of abandoned quarries in relation to a current settlement structure or a protected natural area can create serious obstacles in the pursuit of recovering stone for the repairs of historical monuments from their authentic sources. Keywords: dressed stone, quarry, written sources, old maps, natural resources INTRODUCTION When searching for suitable replacement material for the repair of historic buildings of facing stone masonry, finding the location of the original quarries and verifying the current possibilities of obtaining stone of the same or similar composition and appearance are often among the most important tasks. Even if extraction from the original site is no longer possible, such findings are usually important for the understanding of the history of the object under investigation. For the most important buildings, such as cathedrals, monasteries or old stone bridges, quarrying sites are usually documented in written sources. Often there existed bigger quarries, open and deliberately exploited for the needs of the specific construction site. The owner of a quarry, in such a case, was the investor in the works – a monastery, church chapter, etc. Less important urban, municipal and manor buildings, including 14th International Multidisciplinary Scientific GeoConference SGEM 2014 rural churches, are reported on to a lesser degree and for other common buildings the written documents are even rarer. The amount of surviving written sources, of course, depends on the completeness of archival records and the age of the monument. Detailed written sources from the medieval period are usually preserved only for the most important buildings [8]. In terms of information value and authenticity they are the most valuable sources of direct evidence, especially construction accounts. For facts recorded with a time delay (annals, chronicles, memories of witnesses) or subjective testimonies (biographies, personal correspondence) there is a higher need for critical analysis. Work related to searching, transcribing, possibly translating and finally the proper interpretation of these written sources must be entrusted to an experienced specialist, ideally a historian who is experienced in archive research for the needs of historic construction studies. He should be able to go through all the archival material with potentially interesting content and interpret the findings correctly. In addition to written sources in archival collections there are also visual sources, which can include historical maps, building plans or contemporary drawings, sketches, prints and photographs. While the analysis of earlier written sources usually requires palaeographic training, the visual materials, or reproductions of such, can be studied even by a layman or a specialist from another related field, such as a geologist, historian, restorer or architect. A deeper knowledge of the topic of study is invariably an advantage and sometimes may even be crucial for the correct interpretation. Modern opportunities to work with digital copies of historical maps and plans in a GIS environment, often even in thematic layers, allows direct comparison and verification of the topographic position. CHURCH OF OUR LADY IN KONOJEDY An excellent example of the use of preserved written and pictorial documents for locating original sources of building stone is in those related to the late Baroque Monastery Church of the Assumption of the Virgin Mary in the former convent of the Servites in Konojedy (Litomerice district), from the years 1748 to 1752. The church is a relatively large vaulted nave building constructed mostly of dressed sandstone. Careful study of the church construction history revealed detailed construction accounts, which make it possible to follow the entire progress of construction including the role of all the involved crafts. Exceptionally, the specific locations are referred to by name where the building stone was quarried, both for the conventional stonework and for the production of more demanding architectural elements. [5] Hydrogeology, Engineering Geology and Geotechnics Fig. 1 – Czech Republic, detail from a map of northern Bohemia showing the location of the church building and nearby quarry sites, all of which provided stone (M. Panáček 2014) During the five years of building, a total of 10 quarries are mentioned varying in distance from 1.5 to 30 km from the site. The closest to Konojedy is 2.5 km away in Brusov, where Mesozoic calcareous sandstone and claystone were extracted for use as rough masonry blocks for the common masonry and the foundations of the church. Ashlar masonry was combined with fragments of brick and hard basaltoid Tertiary pyroclastics, the latter acquired in a rock outcrop, 1.5 km away in the village of Bílý Kostelec. Carefully processed blocks forming the base of the church are of more durable Mesozoic quartz sandstone. Besides the already mentioned Brusov they were also imported from the 6 km distant Úštěk and Stranný 7 km away. A total of four different quarries provided the material for the cutting of profiled corniches. For that purpose they used better quality Mesozoic quartz sandstone from quarries in Blíževedly (6 km away), Stranný (7 km), Lovečkovice (9 km), or even from Loubí 20 km away. Mesozoic quartz sandstone from quarries on the outskirts of Úštěk (6 km) was used exclusively for the heads of high pilasters on both the external and interior walls and for the window jambs. It was probably most satisfactory in terms of its composition and workability for these architectural elements. Even more stringent requirements were imposed on the material for profiled door portals. Mesozoic quartz sandstone was brought from the approximately 30 km distant quarry near Seidelberg (today Plešivec near Nedamov). Its quality, especially regarding hardness and abrasion resistance, is undoubtedly confirmed by its use for the paving of the church where it was combined with glauconitic calcareous Mesozoic sandstone from Hrušovany (16 km). Very interesting, but not unusual, is the opening of a new quarry of Mesozoic quartz sandstone in 1750 at Dubová Hora near Dubá (20 km). Unfortunately, however, the purpose for which this material was used is not recorded anywhere. 14th International Multidisciplinary Scientific GeoConference SGEM 2014 With the help of the detailed survey maps of 1843 (Fig. 2-5), it has been possible to accurately trace the remains of all the mentioned quarry sites. Their situation related to the location of the church building is shown in Figure 1. Although these maps are almost a hundred years later, they usually reflect the current status of older historical development such as these quarries which were exploited for very long periods. In some places mentioned a single quarry was discovered, while in others, such as at Dubová Hora, there are several possible sites. This probably indicates a long tradition in stone quarrying in this area, with small quarries dispersed at various sites. The quarry in Plešivec is no longer depicted on the map from 1843 as a pictogram, but east of the village there are two places with the local name Steinbruch (meaning Quarry in German). Identified quarries used in the construction of the church in Konojedy also represent several different types of quarrying methods, which are typically found in the Bohemian Cretacious Basin. The quarry in Brusov (Fig. 2) represents a widespread tradition of a small local source found at the edge of a minor village. It used horizontal excavating which is easiest where moderately protruding hillocks reveal solid sedimentary bedrock. Such quarries were used over a long period for the common local buildings and constructions and they are very often found in the North Bohemian region. Slightly different is the method of extraction or utilization of natural relief at the quarry in Loubí (Fig. 3), where there is a gradual excavation of the rock revealed by erosion processes in the form of terraces above the stream meandering in the valley. The centre of the village is located at the top, on a plateau with fertile farmland, while the quarry was opened in the valley at the base of the cliff wall, next to a long-distance communication route. A variant of this type are the quarries in the town of Úštěk (Fig. 4) where urban settlements spread in such a way that the quarries were left immediately behind residential houses lined up along the valley road in front of the rock walls. It is assumed that the houses built adjacent to the rock housed people employed in the quarries directly behind them.